Mobile wireless communications device with shunt component and related methods

ABSTRACT

A mobile wireless communications device may include a portable housing including at least one electrically conductive housing portion configured to function as an antenna. The mobile wireless communications device may also include a printed circuit board (PCB) carried by the portable housing, and wireless transceiver circuitry carried by the PCB and including at least one circuit element carried by the PCB. The mobile wireless communications device may also include at least one current shunt component coupled between the at least one electrically conductive housing portion and the at least one circuit element.

RELATED APPLICATION

The present application is based upon previously filed copendingprovisional application Ser. No. 61/367,113, filed Jul. 23, 2010, theentire subject matter of which is incorporated by reference in itsentirety.

TECHNICAL FIELD

The present disclosure generally relates to the field of wirelesscommunications systems, and, more particularly, to mobile wirelesscommunications devices and related methods.

BACKGROUND

Mobile wireless communications systems continue to grow in popularityand have become an integral part of both personal and businesscommunications. For example, cellular telephones allow users to placeand receive voice calls almost anywhere they travel. Moreover, ascellular telephone technology has increased, so too has thefunctionality of cellular devices and the different types of devicesavailable to users. For example, many cellular devices now incorporatepersonal digital assistant (PDA) features such as calendars, addressbooks, task lists, etc. Moreover, such multi-function devices may alsoallow users to wirelessly send and receive electronic mail (email)messages and access the Internet via a cellular network and/or awireless local area network (WLAN), for example.

Even so, as the functionality of cellular communications devicescontinues to increase, so too does the demand for smaller devices whichare easier and more convenient for users to carry. One challenge thisposes for cellular device manufacturers is designing housings thatcooperate with antennas to provide desired operating characteristicswithin the relatively limited amount of space available.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a mobile wireless communications deviceincluding a shunt conductor in accordance with one exemplary aspect.

FIG. 2 is a schematic diagram of the printed circuit board (PCB) and thehousing of the device of FIG. 1.

FIGS. 3 a-3 d are schematic diagrams of circuit elements and a shuntconductor in accordance with exemplary embodiments.

FIG. 4 is a schematic diagram of an arrangement of passband and stopbandcells in accordance with an exemplary embodiment.

FIG. 5 is a cross-sectional diagram of a multi-layer PCB in accordancewith an exemplary embodiment.

FIG. 6 is a graph of measured radiation of an antenna of a mobilewireless communication device in accordance with an exemplaryembodiment.

FIG. 7 is a schematic diagram of a portion of a PCB and housing of amobile wireless communications device in accordance with an exemplaryembodiment.

FIG. 8 is an enlarged view of a portion of the PCB and housing of FIG.7.

FIG. 9 is a schematic block diagram illustrating additional componentsthat may be included in the mobile wireless communications device ofFIG. 1.

DETAILED DESCRIPTION

The present description is made with reference to the accompanyingdrawings, in which various embodiments are shown. However, manydifferent embodiments may be used, and thus the description should notbe construed as limited to the embodiments set forth herein. Rather,these embodiments are provided so that this disclosure will be thoroughand complete. Like numbers refer to like elements throughout and primenotation is used to indicate similar elements in alternativeembodiments.

In accordance with one exemplary aspect, a mobile wirelesscommunications device may include a portable housing including at leastone electrically conductive housing portion configured to function as apart or as a whole of an antenna. The mobile wireless communicationsdevice may also include a printed circuit board (PCB) carried by theportable housing, and wireless transceiver circuitry including at leastone circuit element carried by the PCB. The mobile wirelesscommunications device may also include at least one current shuntcomponent coupled between the at least one electrically conductivehousing portion and the at least one circuit element. Accordingly, themobile wireless communications device may provide an increaseddirectional radiation pattern and reduced losses from the portablehousing.

The PCB and the at least one electrically conductive portion may bepositioned to define an air gap therebetween, for example. The mobilewireless communications device may further include a dielectric materialbody between the PCB and the at least one electrically conductivehousing portion.

The at least one electrically conductive housing portion may include anelectrically conductive ring along a perimeter of the portable housing,for example. The at least one current shunt component may include aplurality of current shunt components.

The at least one circuit element may include at least one conductivetrace. The at least one electrically conductive portion may include atleast one metallic material housing portion, for example.

The at least one circuit element may include at least one programmablecircuit element. The at least one circuit element may include aplurality of impedance elements coupled together at a common node. Theat least one current shunt component may be coupled to the common node,for example.

The at least one circuit element may also include at least one inductor,for example. The at least one circuit element may further include atleast one capacitor.

The at least one current shunt component may also include at least oneinductor. The at least one current shunt component may also include atleast one capacitor, for example.

A method aspect may be directed to a method of making a mobile wirelesscommunications device that may include a portable housing comprising atleast one electrically conductive housing portion configured to functionas an antenna, a printed circuit board (PCB) carried by the portablehousing, and wireless transceiver circuitry carried by the PCB andincluding at least one circuit element carried by the PCB. The methodmay include coupling at least one current shunt component between the atleast one electrically conductive portion and the at least one circuitelement, for example.

Referring initially to FIGS. 1-3, a mobile wireless communicationsdevice 30 illustratively includes a portable housing 31, a printedcircuit board (PCB) 32 carried by the portable housing, and wirelesstransceiver circuitry 33 carried by the portable housing. In otherembodiments, the PCB 32 may be used in conjunction with a metal chassisor other substrate. The PCB 32 may also include a conductive layerdefining a ground plane (not shown).

A satellite positioning signal receiver 34 is also carried by theportable housing 31. The satellite positioning signal receiver 34 may bea Global Positioning System (GPS) satellite receiver, for example.

The exemplary device 30 further illustratively includes a display 60 anda plurality of control keys including an “off hook” (i.e., initiatephone call) key 61, an “on hook” (i.e., discontinue phone call) key 62,a menu key 63, and a return or escape key 64. Operation of the variousdevice components and input keys, etc., will be described further belowwith reference to FIG. 9.

A controller 66 or processor may also be carried by the PCB 32. Thecontroller 66 may cooperate with the other components, for example, theantenna 35, the satellite positioning signal receiver 34, and thewireless transceiver circuitry 33 to coordinate and control operationsof the mobile wireless communications device 30. Operations may includemobile voice and data operations, including email and Internet data.

The portable housing 31 includes an electrically conductive portion. Forexample, the portable housing 31 may be metallic or include a metallicportion. As will be appreciated by those skilled in the art, when aportable housing 31 includes an electrically conductive portion, theelectrically conductive portion functions as an antenna, and controllingthe direction of current flowing the antenna becomes increasinglydifficult.

The portable conductive housing 31 including the electrically conductiveportion configured to operate as an antenna may transmit or receive atdifferent operating frequencies, for example, cellular telephone,satellite, or other wireless communications frequencies. The mobilewireless communications device 30 may include an additional or secondantenna 35 coupled to the wireless transceiver circuitry 33. The secondantenna 35 may also be configured to transmit or receive at differentoperating frequencies, for example, cellular telephone, satellite, orother wireless communications frequencies, and may operate independentlyor in conjunction with the electrically conductive portion of theportable conductive housing 31 that is configured as an antenna.

One particularly advantageous approach to controlling the current flowincludes forming a non-current carrying portion, using the portablehousing 31 (configured as an antenna) and circuit elements 36 configuredin an array. The circuit elements 36 may include orthogonal circuitcomponents, for example, one or more of a capacitor and inductor. Thecircuit elements 36 may also include conductive traces, for example, onthe PCB 32. The circuit elements 36 may be other components or elements,as will be appreciated by those skilled in the art.

At each common node or intersection 37 of the circuit elements 36, ashunt component 38 is coupled to the portable housing 31. Theintersection of four circuit elements 36 and the shunt component 38extending from the intersection 37 form a unit cell 40. As will beappreciated by those skilled in the art, the non-current carryingportion is formed by the cooperation of the array of circuit elements 36and a shunt component 38. In other words, unit cells 40 may be used todefine a current path for the current. For example, as illustrated inFIG. 3 a, a unit cell 40 configured as a passband unit cellillustratively includes four inductors as the circuit elements 36 and acapacitor as the shunt component 38. Alternatively, as illustrated inFIG. 3 b, a unit cell 40′ configured as a stopband unit cellillustratively includes four capacitors as the circuit elements 36′ anda capacitor as the shunt component 38′. Of course, other types ofcircuit elements 36 and shunt conductors 38 may be used, for example, asillustrated in FIGS. 3 c and 3 d, and the shunt conductor may includemore than one shunt conductor.

Additionally, when the spacing between adjacent circuit elements 36 isrelatively much less than the desired operating wavelength, the unitcell 40 may exhibit electromagnetic characteristics that may be adjustedto desired specifications. Accordingly, unit cells 40 including thecircuit elements 36 and the shunt conductor 38 may be characterized bymacro quantities, such as permittivity or permeability, for example.Using the quasi-transverse electromagnetic mode (quasi-TEM)approximation within a unit cell 40, as disclosed in J. K. H. Wong, K.G. Balmain, and G. V. Eleftheriades, “Fields in planar anisotropictransmission-line metamaterials,” vol. 54, no. 10, pp. 2742-2749,October 2006, the non-zero field components are:

∂Ez/∂y=jωμ _(xx) H _(x)  (1a)

∂Ez/∂x=jωμ _(yy) H  (1b)

−∂Hx/∂y+∂Hy/∂x=jω

_(zz) E _(z).  (1c)

This configuration allows the propagation of waves where the electricfields are polarized vertically between the unit cells 40 and theportable housing 31. If the separation between the unit cells 40 and theportable housing 31 is made sufficiently small, the fields within thevolume bounded by the unit cells and the portable housing isapproximately uniform in the z direction. In other words, ∂/∂z=0 andequations (1a-1c) apply. Considering the H-mode fields, equations (1a)and (1b) are integrated to obtain:

∂V _(z)/∂_(y) =−jωμ _(xx) H _(x) Δz  (2a)

∂V _(z)/∂_(x) =jωμ _(yy) H _(y) Δz.  (2b)

Next, equation (2) is integrated along the x and the y directions toobtain:

∂V _(z)/∂_(y)Δ_(x) =−jωμ _(xx) I _(y) Δz  (3a)

∂V _(z)/∂_(x)Δ_(y) =jωμ _(yy) I _(x) Δz.  (3b)

The currents flowing through the circuit elements 36, i.e. thecapacitors and the inductors are determined by the voltage differenceacross a unit cell 40 and can be expressed as:

I _(x)=(1/jX _(x))(∂V _(z) /∂x)(Δx)  (4a)

I _(y)=−(1/jX _(y))(∂V _(z) /∂y)(Δy).  (4b)

In equations (4a-4b), X_(x) and X_(y) are respectively, the reactancealong the x and the y directions at the wave frequency. Substitutingequation (4) into equation (3) and assuming d=Δx=Δy=Δz:

μ_(xx) =X _(y) /ωd  (5a)

μ_(yy) =X _(x) /ωd  (5b)

For the unit cell 40 illustrated in FIG. 3 a, the reactance along the xand the y directions are equal and can be represented as

X _(x) =X _(y) =ωL ₀ d+ωL  (6)

where L is the series loaded inductance and L₀ is the inductance perunit length of the interconnecting transmission line. Therefore,equation (6) can be substituted into equation (5) to arrive at theexpressions that relate the permeabilities and the lumped componentvalues which is:

μ_(xx)=μ_(yy) =L ₀ +L/d  (7)

Applying the same procedure to the Ampere's law, (1c), one would arriveat an expression relating the shunt component 38 value to thepermittivity which is:

_(zz) =C ₀ +C _(shunt) /D  (8)

where C_(shunt) is the shunt capacitance and C₀ is the capacitance perunit length of the interconnecting transmission-line.

Having calculated the effective permittivity and the permeability, thepropagation constant within the portable housing 31 and the array ofcircuit components 36 may be derived such that:

k=ω√(μ

)=ω√(L ₀ +L/d)(C ₀ +C/d)  (9)

Assuming that the operating frequency is relatively well below theself-resonance frequency of the circuit components 36 (i.e., theinductors and the capacitors), equation (9) is always real. In otherwords, propagation is allowed for all frequencies from zero to theself-resonance frequency of the circuit components 36. Thus, theportable housing 31, the circuit elements 36 (i.e. series inductors),and the shunt component 38 cooperate to form a passband condition (FIG.3 a).

To create a stopband condition, k must be made imaginary. Accordingly,if the circuit component 36′ is a capacitor as shown in FIG. 3 b. we get

X _(x) =X _(y) =ωL ₀ d−1/ωC  (10)

Substituting equation (10) into equation (5):

μ_(xx)=μ_(yy) =L ₀−1/ω² Cd  (11)

Thus, propagation in such as structure is given by

k=ω√(μ

)=ω√(L ₀−1/ω² Cd)(C ₀ +C/d))  (12)

From (12), one can observe that the wave vector becomes imaginary whenthe following condition holds

C<1/ω² L ₀ d  (13)

In other words, a stopband condition can be achieved within a desiredfrequency range by varying C. As will be appreciated by those skilled inthe art, to create a stopband, any number or combination of circuitcomponents may be used so long as k is imaginary. Additionally, acombination of passband unit cells 40 and stopband unit cells 40′ may beconfigured to direct currents from the antenna 35.

Referring now to FIG. 4, a combination of passband and stopband unitcells 40, 40′, 40″, 40′″ may be arranged to direct the flow of currentthrough the portable housing 31. When the portable housing 31 is excitedwith current from the antenna 35, the current will flow away from thepoint of excitation, but may be confined by the stopband unit cells 40′and flow in areas of the passband cells 40. Thus, as will be appreciatedby those skilled in the art, antenna design in a device having a fullmetal portable housing may focus on the arrangement of the passband unitcells 40 into a shape and size that produces the desired radiationpattern.

However, given the relatively small size of a mobile wirelesscommunications device 30, it may be desirable to further reduce theamount of discrete physical components used for directing the current orcreating the non-current carrying portion. In other words, a mobilewireless communications device 30 including an array, or a layer, ofcircuit elements 36 may not be desirable, as additional components mayincrease the weight of the mobile wireless communications device. Insuch a case, the circuit elements 36 may be the circuit componentscarried on the PCB 32, for example, the wireless transceiver circuitry33.

As will be appreciated by those skilled in the art, the array of spacedapart circuit components 36 and the shunt component 38 advantageouslycooperate to enable radiation with a mobile wireless communicationsdevice having an electrically conductive housing. Indeed, growingindustrial design trends include metallic materials, for example, toconvey a sense of increased quality.

Accordingly, many mobile wireless communications devices includerelatively increased quantities of metallic materials. Some of thesemobile wireless communications devices also include a radiating element,or an antenna, that is integrated into a structure including themetallic materials, for example, a metal ring. In other words, the metalring or electrically conductive material portion of the portable housingalso functions as an antenna. Alternatively, in some mobile wirelesscommunications devices, the radiating element may be positioned awayfrom the metallic materials (e.g. metallic housing).

The circuit components 36 and the shunt component 38 advantageouslyenable wireless communications via an internal antenna that may becompletely covered with a metallic material, for example. Indeed, aswill be appreciated by those skilled in the art, a metallic material mayinclude a material that behaves like a conductor in the radio frequency(RF) band. For example, a metallic material may include a liquid crystaldisplay (LCD), as the glass is embedded with micro-wires that wouldappear as a conducting plate to an electromagnetic wave.

Referring now to FIG. 5, in another exemplary embodiment, the mobilewireless communications device 30″″ includes a multi-layer PCB 32″″ thatincludes a first conductive layer 51″″ (i.e. the ground plane), adielectric layer 54″″, and a second conductive layer 52″″ separated fromthe first conductive layer by a second dielectric layer 53″″. The seconddielectric layer 53″″ may be a layer of air, or may be anotherdielectric material, as will be appreciated by those skilled in the art.The shunt conductor 38″″ couples the first and second conductive layers51″″, 52″″. The second conductive layer 51″″ may include the circuitelements 36″″ or conductive traces (not shown) on the PCB 32″″.

Still further, in some exemplary embodiments, one or more of the circuitelements 36 may be carried by a flexible substrate (not shown). Theflexible circuit substrate, which may be either attached to the PCB 32or separate from the PCB, may carry the circuit elements 36 or include ametallization layer that acts as the circuit elements. The flexiblecircuit substrate may be Kapton™, for example.

A prototype mobile wireless communications device similar to the mobilewireless communications device 30 described above was made and coveredwith copper to emulate a completely metallic portable housing. Theantenna was configured for operation at the GPS frequency of 1.575 GHz.The PCB had a plurality of shunt components configured in asemi-circular configuration and coupling the metallic portable housingto the ground plane of the PCB.

Referring additionally to the graph 71 in FIG. 6, the measured radiationpattern of the prototype GPS antenna of the prototype is illustrated.The measured gain is roughly −7.5 dBi, which is relatively comparablewith the antenna gain of other GPS antennas.

Referring now to FIGS. 7-8, another embodiment of the mobile wirelesscommunications device 130 according to an exemplary aspect is described.Illustratively, the portable housing 131 includes a metal ring 145positioned along a perimeter of the portable housing and configured tofunction as a part of an antenna. The metal ring 145 causes increaseddegradation in radiated performance from the hand phantom condition, aswill be appreciated by those skilled in the art. A relatively largemagnitude of current was found to flow in the metal ring 145 where theuser's hand would come into contact therewith. As such, a majority ofthe current or radiation was directed into the user's hand.

To reduce the current flowing on the metal ring 145 with a relativelysmall, if any, reduction in antenna radiation performance, a non-currentcarrying portion is adjacent the side of the mobile wirelesscommunications device 130. The non-current carrying portion, is createdby cooperation between the metal ring 145, the PCB 132, and the antennafeed location.

The metal ring 145 makes contact with the PCB 132 via the screw mounts146 around the metal ring. The non-current carrying portion is achievedby isolating the screw mounts 146 near the antenna feedpoint. Thenon-current carrying portion length is defined by distance between thegrounding points (i.e. the other three screw mounts that are not coupledto the shunt components 138) and the loading elements, or the shuntcomponents, along the non-current carrying portion. To create thenon-current carrying portion, the shunt components 138 that couple themetal ring 145 to the PCB 132 are adjusted such that the propagationconstant along the metal ring becomes imaginary. Additionally, an airgap 149 is between the PCB 132 and the metal ring 145 along thenon-current carrying portion.

Referring now to Tables 1 and 2, the results of two measurementsperformed, one with a non-current carrying portion in accordance withthe present embodiments, (Table 1) and another without a non-currentcarrying portion (Table 2), are shown. Indeed, as will be appreciated bythose skilled in the art, the measurements show that the hand-phantomperformance of the non-current carrying portion implementation is animprovement across the bands with as much as 5 dB.

TABLE 1 Tx Rx Band L M H L M H 1800 −10.44 −10.23 −10.88 −10.98 −10.97−11.61 1900 −11.20 −11.69 −11.48 −12.10 −12.33 −12.62 2100 −11.83 −12.24−11.96 −11.96 −13.38 −15.61

TABLE 2 Tx Rx Band L M H L M H 1800 −9.66 −9.12 −9.47 −9.65 −8.86 −9.061900 −8.90 −9.10 −8.23 −8.77 −8.23 −8.44 2100 −8.44 −8.57 −7.83 −8.50−8.75 −8.63

In some embodiments, not shown, the non-current carrying portion, may beprogrammable. In other words, the non-current carrying portion may notbe limited to a fixed range of frequencies. As will be appreciated bythose skilled in the art, the shunt components 38 allow fine-tuning ofthe wave vector. Accordingly, the shunt components 38 may be replaced bya programmable network device, such as may be available from MurataManufacturing, Co. Ltd. of Japan, or Epcos AG of Germany.

In contrast to the mobile wireless communications device describedherein, the iPhone™ 4G, for example, which also uses its inherentstructural metal band as a radiating element, uses a broken structure asa radiating element or antenna. Indeed, the metal ring 145 of thepresent embodiments encompasses the entire perimeter of the mobilewireless communications device 130, and there are no cuts or partinglines in the metal ring. Accordingly, the integrity of the portablehousing 131 remains intact.

Moreover, the iPhone™ 4G uses a broken structure band as its radiatingelement, and is tuned to several frequencies. In contrast, in thepresent embodiments, a portion of the structure is responsible forradiation. This is achieved by reducing the two-dimensional (2D)non-current carrying portion approach into a one-dimensional (1D) form.

Existing approaches for wirelessly communicating using a mobile wirelesscommunications device having a full metal housing or enclosure weredeveloped for aircrafts, missiles, land/naval armored vehicles, or radarsystems, for example, as disclosed by F. D. Bennett, P. D. Coleman, andA. S. Meier in, “The design of broadband aircraft-antenna systems,”Proceedings of I.R.E., pp. 671-700, October 1954, and by H. G. Booker in“Slot aerials and their relation to complementary wire aerials(Babinet's principle),” Journal of I.E.E., no. 93, p. 620, 1946. Theseapproaches employed either slots (magnetic currents) or externalantennas for controlling the radiation pattern. Magnetic currents can becreated by slots or an aperture in a conductive plate. This method isrelatively more difficult to implement in a mobile wirelesscommunications device, as the slot length is restricted by the devicesize and the industrial design requirements.

Furthermore, in a mobile wireless communications device environment, aPCB may act like a ground plane, where the propagating power is trappedby the parallel-plate TEM mode that degrades the overall radiationefficiency. Alternatively, an external antenna may be used; however,this would be contrary to the current industrial design trend, where itis desirable that all antennas be internal to the device housing.

A method aspect is directed to a method of making a mobile wirelesscommunications device 30 that includes a portable housing 31 includingat least one electrically conductive housing portion configured tofunction as an antenna, a printed circuit board (PCB) 32 carried by theportable housing, and wireless transceiver circuitry 33 carried by thePCB and including at least one circuit element 36 carried by the PCB.The method includes coupling at least one current shunt component 38between the at least one electrically conductive portion 31 and the atleast one circuit element 36.

Exemplary components that may be used in various embodiments of theabove-described mobile wireless communications device are now describedwith reference to an exemplary mobile wireless communications device1000 shown in FIG. 9. The device 1000 illustratively includes a housing1200, a keypad 1400 and an output device 1600. The output device shownis a display 1600, which may comprise a full graphic LCD. In someembodiments, display 1600 may comprise a touch-sensitive input andoutput device. Other types of output devices may alternatively beutilized. A processing device 1800 is contained within the housing 1200and is coupled between the keypad 1400 and the display 1600. Theprocessing device 1800 controls the operation of the display 1600, aswell as the overall operation of the mobile device 1000, in response toactuation of keys on the keypad 1400 by the user. In some embodiments,keypad 1400 may comprise a physical keypad or a virtual keypad (e.g.,using a touch-sensitive interface) or both.

The housing 1200 may be elongated vertically, or may take on other sizesand shapes (including clamshell housing structures, for example). Thekeypad 1400 may include a mode selection key, or other hardware orsoftware for switching between text entry and telephony entry.

In addition to the processing device 1800, other parts of the mobiledevice 1000 are shown schematically in FIG. 9. These include acommunications subsystem 1001; a short-range communications subsystem1020; the keypad 1400 and the display 1600, along with otherinput/output devices 1060, 1080, 1100 and 1120; as well as memorydevices 1160, 1180 and various other device subsystems 1201. The mobiledevice 1000 may comprise a two-way RF communications device having voiceand data communications capabilities. In addition, the mobile device1000 may have the capability to communicate with other computer systemsvia the Internet.

Operating system software executed by the processing device 1800 may bestored in a persistent store, such as the flash memory 1160, but may bestored in other types of memory devices, such as a read only memory(ROM) or similar storage element. In addition, system software, specificdevice applications, or parts thereof, may be temporarily loaded into avolatile store, such as the random access memory (RAM) 1180.Communications signals received by the mobile device may also be storedin the RAM 1180.

The processing device 1800, in addition to its operating systemfunctions, enables execution of software applications or modules1300A-1300N on the device 1000, such as software modules for performingvarious steps or operations. A predetermined set of applications thatcontrol basic device operations, such as data and voice communications1300A and 1300B, may be installed on the device 1000 during manufacture.In addition, a personal information manager (PIM) application may beinstalled during manufacture. The PIM may be capable of organizing andmanaging data items, such as e-mail, calendar events, voice mails,appointments, and task items. The PIM application may also be capable ofsending and receiving data items via a wireless network 1401. The PIMdata items may be seamlessly integrated, synchronized and updated viathe wireless network 1401 with the device user's corresponding dataitems stored or associated with a host computer system.

Communication functions, including data and voice communications, areperformed through the communications subsystem 1001, and possiblythrough the short-range communications subsystem. The communicationssubsystem 1001 includes a receiver 1500, a transmitter 1520, and one ormore antennas 1540 and 1560. In addition, the communications subsystem1001 also includes a processing module, such as a digital signalprocessor (DSP) 1580, and local oscillators (LOs) 1601. The specificdesign and implementation of the communications subsystem 1001 isdependent upon the communications network in which the mobile device1000 is intended to operate. For example, a mobile device 1000 mayinclude a communications subsystem 1001 designed to operate with theMobitex™, Data TAC™ or General Packet Radio Service (GPRS) mobile datacommunications networks, and also designed to operate with any of avariety of voice communications networks, such as AMPS, TDMA, CDMA,WCDMA, PCS, GSM, EDGE, etc. Other types of data and voice networks, bothseparate and integrated, may also be utilized with the mobile device1000. The mobile device 1000 may also be compliant with othercommunications standards such as GSM, 3G, UMTS, 4G, etc.

Network access requirements vary depending upon the type ofcommunication system. For example, in the Mobitex and DataTAC networks,mobile devices are registered on the network using a unique personalidentification number or PIN associated with each device. In GPRSnetworks, however, network access is associated with a subscriber, oruser of a device. A GPRS device therefore utilizes a subscriber identitymodule, commonly referred to as a SIM card, in order to operate on aGPRS network.

When required network registration or activation procedures have beencompleted, the mobile device 1000 may send and receive communicationssignals over the communication network 1401. Signals received from thecommunications network 1401 by the antenna 1540 are routed to thereceiver 1500, which provides for signal amplification, frequency downconversion, filtering, channel selection, etc., and may also provideanalog to digital conversion. Analog-to-digital conversion of thereceived signal allows the DSP 1580 to perform more complexcommunications functions, such as demodulation and decoding. In asimilar manner, signals to be transmitted to the network 1401 areprocessed (e.g. modulated and encoded) by the DSP 1580 and are thenprovided to the transmitter 1520 for digital to analog conversion,frequency up conversion, filtering, amplification and transmission tothe communication network 1401 (or networks) via the antenna 1560.

In addition to processing communications signals, the DSP 1580 providesfor control of the receiver 1500 and the transmitter 1520. For example,gains applied to communications signals in the receiver 1500 andtransmitter 1520 may be adaptively controlled through automatic gaincontrol algorithms implemented in the DSP 1580.

In a data communications mode, a received signal, such as a text messageor web page download, is processed by the communications subsystem 1001and is input to the processing device 1800. The received signal is thenfurther processed by the processing device 1800 for an output to thedisplay 1600, or alternatively to some other auxiliary I/O device 1060.A device user may also compose data items, such as e-mail messages,using the keypad 1400 and/or some other auxiliary I/O device 1060, suchas a touchpad, a rocker switch, a thumb-wheel, or some other type ofinput device. The composed data items may then be transmitted over thecommunications network 1401 via the communications subsystem 1001.

In a voice communications mode, overall operation of the device issubstantially similar to the data communications mode, except thatreceived signals are output to a speaker 1100, and signals fortransmission are generated by a microphone 1120. Alternative voice oraudio I/O subsystems, such as a voice message recording subsystem, mayalso be implemented on the device 1000. In addition, the display 1600may also be utilized in voice communications mode, for example todisplay the identity of a calling party, the duration of a voice call,or other voice call related information.

The short-range communications subsystem enables communication betweenthe mobile device 1000 and other proximate systems or devices, whichneed not necessarily be similar devices. For example, the short-rangecommunications subsystem 1020 may include an infrared device andassociated circuits and components, near-field communication (NFC), or aBluetooth™ communications module to provide for communication withsimilarly-enabled systems and devices.

Many modifications and other embodiments will come to the mind of oneskilled in the art having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it isunderstood that the disclosure is not to be limited to the specificembodiments disclosed, and that modifications and embodiments areintended to be included.

1-24. (canceled)
 25. An electronic device comprising: a housingcomprising an electrically conductive continuous closed ring around aperiphery thereof; wireless transceiver circuitry carried by saidhousing and comprising a plurality of circuit elements; and a pluralityof current shunt components carried by said housing and electricallycoupled between said electrically conductive continuous closed ring andcorresponding ones of said plurality of circuit elements to define aplurality of unit cells, the plurality of unit cells configured to causesaid electrically conductive continuous closed ring to have at least onecurrent carrying portion and at least one non-current carrying portion.26. The electronic device according to claim 25, further comprising aprinted circuit board (PCB) carried by said housing and mounting saidwireless transceiver circuitry; and wherein said PCB and saidelectrically conductive closed ring are positioned to define an air gaptherebetween.
 27. The electronic device according to claim 26, furthercomprising a dielectric material body between said PCB and saidelectrically conductive continuous closed ring.
 28. The electronicdevice according to claim 25, wherein said plurality of circuit elementscomprises at least one conductive trace on said PCB.
 29. The electronicdevice according to claim 25, wherein said electrically conductivecontinuous closed ring comprises at least one metallic material portion.30. The electronic device according to claim 25, wherein said pluralityof circuit elements comprises at least one programmable circuit element.31. The electronic device according to claim 25, wherein said pluralityof circuit elements comprises a plurality of impedance elements coupledtogether at a common node with a corresponding current shunt componentalso coupled to the common node for a given unit cell.
 32. Theelectronic device according to claim 25, said plurality of circuitelements comprises at least one inductor.
 33. The electronic deviceaccording to claim 25, said plurality of circuit elements comprises atleast one capacitor.
 34. The electronic device according to claim 25,wherein said plurality of current shunt components comprises at leastone inductor.
 35. The electronic device according to claim 25, whereinsaid plurality of current shunt components comprises at least onecapacitor.
 36. An electronic device comprising: an electricallyconductive continuous closed ring; wireless transceiver circuitrycomprising a plurality of circuit elements; and a plurality of currentshunt components electrically coupled between said electricallyconductive continuous closed ring and corresponding ones of saidplurality of circuit elements to define a plurality of unit cells, theplurality of unit cells configured to cause said electrically conductivecontinuous closed ring to have at least one current carrying portion andat least one non-current carrying portion.
 37. The electronic deviceaccording to claim 36, further comprising a printed circuit board (PCB)mounting said wireless transceiver circuitry; and wherein said PCB andsaid electrically conductive closed ring are positioned to define an airgap therebetween.
 38. The electronic device according to claim 36,wherein said plurality of circuit elements comprises at least oneconductive trace on said PCB.
 39. The electronic device according toclaim 36, wherein said plurality of circuit elements comprises at leastone programmable circuit element.
 40. The electronic device according toclaim 36, wherein said plurality of circuit elements comprises aplurality of impedance elements coupled together at a common node with acorresponding current shunt component also coupled to the common nodefor a given unit cell.
 41. The electronic device according to claim 36,said plurality of circuit elements comprises at least one of an inductorand a capacitor.
 42. The electronic device according to claim 36,wherein said plurality of current shunt components comprises at leastone of an inductor and a capacitor.
 43. A method for making anelectronic device comprising: electrically coupling a plurality ofcurrent shunt components between an electrically conductive continuousclosed ring and corresponding ones of a plurality of circuit elements ofwireless transceiver circuitry to define a plurality of unit cells, theplurality of unit cells configured to cause the electrically conductivecontinuous closed ring to have at least one current carrying portion andat least one non-current carrying portion.
 44. The method according toclaim 43, further comprising mounting the wireless transceiver circuitryon a printed circuit board (PCB) mounting; and positioning the PCB andthe electrically conductive closed ring to define an air gaptherebetween.
 45. The method according to claim 44, wherein theplurality of circuit elements comprises at least one conductive trace onthe PCB.
 46. The method according to claim 43, wherein the plurality ofcircuit elements comprises at least one programmable circuit element;and further comprising programming the at least one programmable circuitelement.
 47. The method according to claim 43, further comprisingcoupling together the plurality of circuit elements at a common nodewith a corresponding current shunt component for a given unit cell. 48.The method according to claim 43, the plurality of circuit elementscomprises at least one of an inductor and a capacitor.
 49. The methodaccording to claim 43, wherein the plurality of current shunt componentscomprises at least one of an inductor and a capacitor.